When it comes to housing, the subject of this eighth post in our Pinning Down Miliband series, the Labour leader sure has plenty of ambition. He spelt out that ambition in his party conference speech last year. “We’ll have a clear aim,” he said, “that by the end of the parliament Britain will be building 200,000 homes a year, more than at any time in a generation.”

Let’s put aside the fact that this “clear aim” later had to be clarified still further – over 200,000 homes were built in Britain in 2007-08; Miliband meant to say England – and it’s quite a decent aim to have. It may not meet the 300,000 homes-a-year level that Policy Exchange recommends to keep up with demand, but it’s still an advance on the 107,820 houses that were completed in the last financial year. In fact, you’ll have noticed, it’s about double that number. That’ll sound good in the election broadcasts.

But before we all grab our hardhats and spades, to join Miliband’s construction crusade, it’s worth asking a simple question: how’s it going to happen? And that’s where Miliband’s “clear aim” slips into further obscurity. As usual, Miliband’s full policy is pending, waiting on a review that’s currently being conducted by Sir Michael Lyons. This review’s prescriptions are still the best part of a year away. For now, Miliband has the blurb, but not the blueprint.

Which isn’t to say we have no idea what a Labour Government’s housing policy would be. Miliband outlined some of his methods for hitting that 200,000 target in the conference speech:

“So we’ll say to private developers, you can’t just sit on land and refuse to build. We will give them a very clear message – either use the land or lose the land, that is what the next Labour government will do. We’ll say to local authorities that they have a right to grow, and neighbouring authorities can’t just stop them. We’ll identify new towns and garden cities and we’ll have a clear aim that by the end of the parliament Britain will be building 200,000 homes a year, more than at any time in a generation.”

A variation on this theme, in December, incorporated a few other potential policies: including a loosening of the financial restrictions imposed on local authorities, and Treasury-backed guarantees for the development of new towns.

One thing that’s striking about Miliband’s sketchy housing agenda is how little upfront Government spending it involves – at least by Labour’s usual standards. That tough-sounding ultimatum, “either use the land or lose the land”, is a case in point. Although it will probably require local authorities to splash out on compulsory purchase orders, it’s not some multi-£billion mega-scheme directed from Downing St. It’s more a legal threat, designed to stimulate results without a fiscal stimulus.

Will it work? Hm, perhaps not. It suits Miliband’s political purposes to paint the country’s biggest housing developers as a bunch of chronic hoarders who don’t want to build cheap accommodation for all – but whilst this caricature contains some truth, it is still a caricature. According to the Home Builders Federation, there are around 300,000 individual plots that have received planning permission but that remain undeveloped. This may sound like a high number, but remember: it’s only a year-and-a-half’s supply of housing under Miliband’s five-year plan. And, besides, it may not even be that. Again according to the HBF, 63 per cent of these plots are under construction, with half of what’s left being “economically unviable”. In their words:

“We estimate that just 72,000 consented plots are un-started and considered economically viable.”

Indeed, there’s a possibility that Miliband will be left with practically nothing to get tough about. The Coalition already has its own policies for getting development going, including a little ol’ initiative called “economic recovery”. That initial 300,000 figure is down from 400,000 a year earlier.

But even if Miliband does have loads of land-banks to stomp all over, there are doubts whether the stomping will do any good. I refer you, my learned friends, to the words of one partner from the law firm Winckworth Sherwood. “Forcibly taking land off house builders into the public sector,” she said, “will undoubtedly face legal challenges.” The Labour leader may regard his aims as clear, but the result could be an unedifying scrum in the courtrooms.

It’s similar with another of the Miliband’s policy proposals: the “right to grow” that he would endow upon local authorities. You can see the purpose behind this. It’s an extension of the “duty to cooperate” that the current Government has written into its planning framework, and which is intended to curb those situations, such as in Stevenage, where a neighbouring council stands in the way of development. But what would this “right” really mean? In his December speech, Miliband made the point that, under the current system, “the only winners have been lawyers, on whom Stevenage has had to spend more than £500,000 since 2001”. But would a “right” really prevent further challenges and further pay-cheques for the lawyers?

This emphasis on “rights” calls to mind the “guarantees” that Gordon Brown came to rely on in the twilight of his premiership – y’know, like the pledge-turned-legal-entitlement that everyone should receive hospital treatment within 18 weeks of referral by a GP. The Economist’s Bagehot column made a fine point about them at the time:

“The trouble is that, if the guarantees are not enforceable by law, they will be weak; but if they are, they may lead to an orgy of litigation.”

Yet the word “guarantee” still appeared 53 times in Labour’s 2010 manifesto; a manifesto that was, incidentally, written by one Edward Samuel Miliband.

That’s not where the Brown stuff ends. If he really is to reach that 200,000 mark, Miliband might have to bank on the “new towns and garden cities” part of his policy agenda – but, boy, if that doesn’t stir up bad memories of the last Government’s eco-town scheme. This, you’ll remember, was intended to create affordable, environmental housing for tens-of-thousands of – how did they put it back then? – hard-working families, but nothing came of it. One problem was the proposed locations for these towns, which, as I noted for Coffee House, were far removed from jobs and transport hubs. Another problem was the opposition these towns faced, culminating in a protest outside Parliament. Towns rarely pop-up – whoosh! – like the politicians would have you believe.

Of course, the country does need more homes, more quickly. Any politician who has this goal, facing obstacles ranging from public disapproval to private sector reluctance, deserves a certain amount of sympathy. But, from where I’m standing, it’s doubtful whether Miliband’s grand ambitions will translate into grand designs. Years of legal wrangling, protest and disappointment are, sadly, a more likely outcome.